an:03936392
Zbl 0584.65033
Regi??ska, Teresa
Convergence of approximation methods for eigenvalue problem for two forms
EN
Apl. Mat. 29, 333-341 (1984).
00149278
1984
j
65J10 47A10 47A55 47A70
external approximation; eigenvalue problem; bilinear forms; spectral approximation; convergence
The eigenvalue problem \(b(u,v)=\lambda a(u,v)\) \(\forall\) \(v\in V\); \(u\in X\), defined by two bilinear forms on a complex vector space V is considered. The form a is supposed to be symmetric and positive definite, b to be continuous with respect to a; X being the closure of V in the a- norm.
The approximation of the considered problem is defined by a sequence of forms \(a_ n\), \(b_ n\) on the space V, with similar properties as a and b, related to a and b by a number of ordering and convergence conditions. By means of the sequence \(a_ n\), an external approximation \(\{X_ n,r_ n,p_ n\}\) of the space X is defined such that \(X_ n=\bar V\) in the \(a_ n\)-norm. Then the general theory of the spectral approximation via (external) approximation of the space is applied.
The main goal of this paper is Theorem 7 giving the convergence of spectral elements (without error bounds). This result covers the classical method of \textit{N. Aronszajn} [Proc. Symposium spectral theory differential problems, 179-202 (1955; Zbl 0067.091)] and generalizes the paper of \textit{R. D. Brown} [Rocky Mt. J. Math. 10, 199-215 (1980; Zbl 0445.49043)] concerning the case when b is symmetric.
K.Moszy??ski
Zbl 0067.091; Zbl 0445.49043